For the most part, getting the lyrics for your foreign-language music is a cakewalk: just search for the translation of the English word "lyrics" in your target language, the name of the artist (in quotes if more than one word), and the song title (again, in quotes if more than one word).
To take an example, if you want to find the lyrics to the song En el muelle de San Blás by the Spanish-language band Maná, Googling:
letra maná "en el muelle de san blás"will get you the lyrics in the first search result, which you can then copy and paste wherever you like.
Japanese lyrics, however, are a bit more complicated, and perhaps surprisingly it's for reasons that have nothing to do with the language itself.